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"We expect to fulfill inventory to meet demands in the coming weeks," a Samsung representative said.

The issues have already affected two U.S. carriers. Sprint Nextel will still offer the phone via its Web site and telesales on April 27, but gave no word on when it would actually have the phone in stores. T-Mobile delayed its launch by five days to April 29, and likewise said it would be limited to online availability.

Supply issues have traditionally been more often Apple's problem, as it has on several occasions faced overwhelming orders for its iPhone franchise. But Samsung has shown that the Galaxy S franchise has been the iPhone's equal in many ways, and now faces a similar inventory issue.

It's a surprising problem for Samsung because the company has historically been good about ensuring that it has enough inventory for a massive global launch. Many of the components and the manufacturing processes are done in-house, so it isn't too beholden to other companies such as Apple.

"Supply chain management is a core differentiator for our brand," Tim Baxter, president of Samsung Electronics America, said during a Samsung-Best Buy event on Wednesday. "It's part of our DNA."

J.K. Shin, head of Samsung's mobile business and co-CEO, told CNET on the sidelines of that event that Samsung chose to offer two different processors on the phone because it wanted to ensure there was a healthy supply of devices, and not create two levels of experience. The two chips have left some wondering if one was significantly faster than the other.

Samsung marketing executive Y.H. Lee previously told CNET that the company considered supply and the ability to quickly ramp up production when choosing plastic over other more complicated materials such as metal or glass.

The slight delay and availability issue may provide an opening to the HTC One, which faced its own delay but is now on sale at three of the four major carriers (with Verizon Wireless opting not to offer the phone).

Like Apple, Samsung is opting for a massive rollout of the phone on 327 carriers across 155 countries. In the U.S., virtually every carrier has committed to selling the phone.

Updated at 12:36 p.m. PT: to include an additional executive quote and background.

CNET's Shara Tibken contributed to this story.

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